Obstetrical forceps



May 21, 1968 A. MISEO OBSTETRICAL FORCEPS 2 Sheets-Sheet 1 Filed July 2, 1965 /2a 42 filllllllll! m m an INVENTOR ANTHONY M1530 ATTORNEYS United States Patent 3,384,088 OBSTETRICAL FORCEPS Anthony Miseo, Bronx, N.Y. (2147 rthur Ave., New York, N.Y. 10457) Filed July 2, 1965, Ser. No. 469,209 7 Claims. (Cl. 128323) ABSTRACT OF THE DISCLOSURE An obstetrical forceps composed of two branches. Each branch includes an elongated handle and a curved blade. Each blade has a hemispherical coupling. The two hemispherical couplings are interengageable to form a ball. Each handle has a socket. The two sockets are interengageable by joining the handles in order to form a cage in which the ball rotates. The sockets are mounted on the handles for rotation about an axis perpendicular to the length of the handles. The ball is constrained for rotation about one axis with respect to the socket. The blades thereby swivel with respect to the handle. Each socket has a passageway. Each coupling has a passageway which can be rotated into alignment with a socket passageway. Each handle has a longitudinally reciprocatable pin, said passageways being mutually aligned with the pin only when the two blades are in a straight line position relative to the handles, so that the pins then can be thrust into the passageways to prevent rotation of both the ball and the sockets and thus render the blades immobile. When the pins are withdrawn from the passageways the blades are freed for swivelling movement. Locking means releasably holds the pins in either of their two positions.

This invention relates to obstetrical forceps.

In my United States Letters Patent No. 2,639,712 granted May 26, 1953 for Obstetrical Forceps, I disclosed an obstetrical forceps having a universal joint between the blades and the handles of the forceps. These forceps permit the blades to rotate during traction and to turn with the head of the child as it descends through the birth canal. This eliminated the necessity during an instrument delivery of removing conventional rigid forceps after a partial descent in the birth canal, rotation of the forceps through 180 and reinsertion of the forceps for the remaining passage through the birth canal. Such reinsertion was a delicate and time-consuming operation and there was always the risk of infection and injury to the babys head.

It is the principal object of my present invention to provide an improved construction in obstetrical forceps having an articulated universal joint between the blades and handles, wherein the blades are free to swivel about two perpendicular axes with respect to the handles in one operative position of the forceps and are lockable so that the blades are held in a rigid straight-line position relative to the handles in another operative position of the forceps.

It is another object of my invention to provide an improved obstetrical forceps of the character described, wherein the components thereof are readily separable and are fashioned for ease in cleaning and sterilization.

It is another object of my invention to provide an improved obstetrical forceps of the character described, wherein the blades thereof are locked through manipulation of two button slides on the handles of the forceps, said button slides being operable by a flick of the operatcrs thumb while his hand is grasping said handles.

It is yet a further object of my invention to provide an improved obstetrical forceps of the character described, wherein separate means is provided to lock in straight-line position each of the blades of said forceps, the forceps being separable into two branches whereby when the Patented May 21, 1968 ICC branches are disunited, each blade can be locked in rigid position with respect to its associated handle.

It is another object of my invention to provide an improved obstetrical forceps of the character described, wherein one of the two blades is hinged to vary the spacing between the blades so as to accommodate infants heads of various sizes, which is characterized by the inclusion of easily manipulable stop means for determining the maximum distance between said blades and for turning the hinge-d blade toward the fixed blade when so desired.

It is still another object of my invention to provide an improved obstetrical forceps of the character described whose components are few in number and simple in manufacture, which can be marketed at a reasonable price in view of the use to which the forceps will be put, and which will be of great benefit in instrument deliveries.

Other objects my invention in part will be obvious and in part will be pointed out hereinafter.

My invention accordingly consists in the features of construction, combinations of elements and arrangements of parts which will be exemplified in the obstetrical forceps hereinafter described and of which the scope of application will be indicated in the appended claims.

In the accompanying drawings in which is shown one of the various possible embodiments of my invention:

FIG. 1 is a top view of my improved obstetrical forceps, the same being constructed in accordance with the present invention;

FIG. 2 is a side view thereof;

FIG. 3 is an enlarged fragmentary view of the end of the interior of a branch of the forceps which carries a blade that is hinged to its swivel mount, the blade being illustrated separated from its associated handle;

FIG. 4- is a view similar to FIG. 3 but illustrating the branch of the forceps carrying a blade that is fixed to its swivel mount;

FIGS. 5 and 6 are enlarged fragmentary sectional views of the forceps taken substantially along the lines, respectively, 5--5 and 66 of, respectively, FIGS. 1 and 2;

FIGS. 7 and 8 are enlarged transverse sectional views of my forceps taken substantially along the lines, respectively, 7-7 and 88 of FIG. 6; and

FIG. 9 is an enlarged sectional view of a portion of my forceps taken substantially along the .line 9-9 of FIG. 5.

Referring now in detail to the drawings, the reference numeral 20 denotes an improved obstetrical forceps embodying my present invention. The forceps includes a pair of detaehably engageable branches, to wit, a first branch 22 and a second branch 24. The first named branch 22 is shown in FIGS. 1, 3, 5 and 6, and the second named branch 24 is shown in FIGS. 1, 2, 4 and 6.

The first branch 22 includes a shank 26 having a handle 28 which has a scalloped portion 30 and which has an outwardly protruding non-rotatable knob 32 located about midway between the ends of the shank, said scalloped portion and said knob facilitating the grasping and manipulation of the branch. The knob 32 has a shaft 34 forcefitted into a bore 36 in said branch.

The interior of the shank 25 is of U-shaped inwardly opening transverse cross-section thereby to receive and mount other elements of the forceps. The branch 22 also carries a hinged blade 38 of conventional forceps contour which is attached to the shank by the articulated universal joint (swivel) to be described.

The second branch 24 also comprises a shank 40 including a handle 42. The handle includes a scalloped portion 44 and an outwardly extending knob 46, the same being fashioned so that the exterior figuration of the branches are substantially mirror images of one another (see FIG. 1). The knob 46 is fixed to the shank 40 in the same way as the knob 32 is fixed to the shank 26.

The shank 49 carries a fixed blade 48 of substantially the same contour as the hinged blade 38, the fixed blade 48 being connected to its associated shank 41 by said articulated universal joint. The interior of the shank 4%) is likewise of U-shaped inwardly opening cross-section to receive and mount other elements of the forceps.

The shanks have their confronting surfaces linear and complementarily shaped so that the two shanks can be readily abutted over their entire lengths.

The fixed blade 48 has a base 50 to which a hemispherical coupling 52 is rigidly secured by a scmicylindrical stub rod 54. The axis of symmetry of said rod is coincident with a major diameter of the coupling 52 and the rod and coupling have truncated faces which are coplanar.

The hinged blade 38 is pivotally carried by a pivot pin 56 mounted on a base, e.g., between the arms of a yoke 58, to which another hemispherical coupling 6 is rigidly secured by another semicylindrical stub rod 62. The rod 54 and the coupling 52 are substantially of the same external shapes and dimensions as the rod 62 and the coupling 60 and said rods and couplings have their truncated confronting faces of complementary shape so that when these parts are placed face to face, the couplings form a ball B (FIG. 6) connected by a cylindrical rod R to the bases of the two blades.

The base 50 of the blade .8 is formed with a cavity 64 to accommodate and permit the pivot end of the blade 33 to rotate without interference and to receive the arms of the yoke 58.

Means is provided to detachably engage the hemispherical couplings 52, 60 and their associated stub rods, respectively, 54, 62. To this end, the truncated faces of one of the couplings 60, its associated rod 62 and the yoke 58 have as an integral part thereof an elongated key 66 (FIGS. 3, 7 and 8) of uniform rectangular transverse cross section with a rounded end 63 distant from the blade 38. The length of said key extends in a direction parallel to the central axis of the associated branch 22.

The truncated faces of the other coupling 52, its associated rod 54 and the base 50 have formed therein an elongated groove (FIGS. 4, 7 and 8) with a rounded end 72, said groove being configured to snugly receive the key 66 and so that the faces of the couplings, stub rods and base and yoke meet face to face.

The rounded end 68 of the key 66 carries a guide pin 74 (FIG. 6) and the rounded end of the groove 70 contains a small bore 76 to receive said pin.

The base 56 of the fixed blade 48 includes a pair of transversely registered open ended slots 78 each disposed on a different side of said blade. Between the arms of the yoke 58 is fixed a guide shaft 80 the ends of which can be received by the slots '78.

To engage the couplings 52, 60, the key 66 of the hinged blade 38 is located in the groove 74 with the round end of the key spaced from the round end of the slot and then these parts are slid relative to one another until positioned so that the guide pin 74 is in the bore 76, While simultaneously the guide shaft 80 is received by the slots 78 of the fixed blade 48.

Each coupling 52, 60 is provided with a narrowmouthed but deep groove 82, the depth of the groove running parallel to the axis of the stub rod 54. The grooves sweep through semicircles of the same radius that, when the couplings are interen aged, jointly define a full continuous circle having an axis coincident with the axis of the ball B parallel to the key 66. Said continuous annular groove circumscribes the ball about a circle smaller than a great circle, this smaller circle being in a plane perpendicular to the longitudinal axis of the rod R. The groove 82 is located on the hemisphere of the ball B closest to the blades 33, 48.

Each coupling is similarly mounted in its associated shank and accordingly the mounting structure for only one of the hemispherical couplings, i.e., the coupling 52, will be described in detail. The components of the other mounting for the other coupling 60 are denoted by the same reference numerals primed.

The coupling 52 has a key pin 84 (FIGS. 4 and 6) slidably received in its semicircular groove 82, the key pins, 84, 84 being diametrically opposed. The coupling 52 is situated in a hemispherical socket 86, the two sockets 85, 86 being alike, contacting and facing one another and defining a spherical cage to slidably rotatably receive the ball B. The key pins 84, 84 are rigidly secured to the sockets 86, $6, each one to a different socket, with the pins having their lengths parallel to the longitudinal axis of the key 66 and with the bases of the pins fixed to the sockets near the rods 54, 62 with the pins situated to be received in the grooves 82, 82 so as to limit rotation of the ball B relative to the sockets 86, 86 to about an axis coincident with the central axis with the rod R. The socket 86 has an open semicircular neck 88 proximate to the blade 48, the necks 83, 88' allowing passage of the juxtaposed stub rods 54, 62.

Integral with and extending outwardly from each socket 86 is a pivot post 90 (FIG. 6) whose outer end is threaded for engagement in a tapped bore 92 of a cap 94 where it is held by a set screw 96 (FIG. 8). The proximate end of the shank 46 is formed with an opening which rotatably passes the pivot post 96 and the socket 86 has a fiat exterior face 89, distant from the opposed socket 86', which rotatably abuts the flat interior face of the shank 40, the cap 94 being on the exterior of the shank and the socket 86 being on the interior of the shank. The end of the shank 40 is formed to prevent interference with the rotative movement of the sockets 36, 86' about the axis of the registered posts 90.

The hemispherical couplings 52, 60 are free to rotate about the axis of the pivot posts 36, 90', such rotation being accompanied by corresponding rotation of the caps 94, 94' and the sockets 86, 86, the key pins 84, S4 linking the ball 8 to the sockets for this purpose. The aforesaid rotation is limited only by the abutment of the rod R against the edges of the notches 8, 98 (FIG. 1) on the proximate ends of the shanks. Rotative movement of blades with their respective couplings about the axis of the pivot posts 90, 90 is illustrated by dot and dash lines in FIG. 2.

As noted above the blades are also free to rotate about the central axis of the rod R. This axis of rotation passes perpendicularly through the axis of the pivot posts and rotation is unlimited in either direction. Said rotation is enabled by the rotation of the ball B in the sockets 86, 86', the key pins 84, 84 sliding in the grooves, 82 as said ball rotates.

Separate means is included to positively lock each of the sockets and its associated hemispherical coupling, and thus its blade, rigid in straight-line position. Such positive lock when engaged will prevent accidental turning of the ball B about any axis, even when during use the parts of the forceps are coated with body fluids that might permit a friction lock to slip. Each of said locking means is alike and accordingly only the one for the coupling 52 will be described, the parts of the other one for the coupling 64 being denoted by the same reference numerals primed.

Each of said means include an elongated bar 100 mounted for free sliding movement within a hollow portion of theshank 40 which is adjacent the socket 86. Except for a head, later described, the bar is somewhat narrower than the inside of the shank 40 so that it is spaced from the walls thereof as shown in FIG. 4. The end of the bar 100 distant from the socket includes a transverse bore in which a shaft 102 is fixed and centered. The ends of the shaft from the bar protrude, pass through two elongated aligned slots 104 in opposed walls of the U-shaped shank and terminate in slide buttons 106. The buttons are located on the exterior of the shank.

The other end of the bar 100 is guided in its sliding movement by a spring clip 108 one end of the base of which is firmly secured, as by a small screw 110, to an intermediate outwardly facing surface of the bar 100. The spring clip 108 is so configured in repose that the free end 112 thereof is spaced further than the nearby surface of the wall of the shank 40. Said free end 112 of the clip is formed with an outwardly protruding cross rib that rides in an elongated track 114 (FIGS. 5 and 9) formed on the interior face of an adjacent wall of the shank 40 (see FIG. 9). The rib is flexed inwardly upon insertion of the bar. into the shank so that it presses against the base of the track 114. Said track 114 has two transverse detent grooves 116, one formed adjacent each end of the track. The free end 112 of the clip drops into one of these detents at the terminus of the movement of the bar 100 in either direction thereby setting the proper limits of movement for said bar.

Located between the ends of the spring clip and in one piece therewith is a retroverted fingernail catch 118 by which said spring clip may be sprung out of the groove 114 towards the bar 100. The catches 118, 118' are exposed when the branches are disengaged (FIGS. 3 and 4) and the spring clip also includes in one piece therewith a small retaining plate 119 (FIG. 5), said plate being located on the side of the bar opposed to the catch 118.

The bar 100 may be swung away from the shank 40 by first urging the catch 118 towards the bar 100 so that the free end 112 of the spring clip 108 is moved out of the track 114 and then rotating the bar 100 with the shaft 102 in the slots 104. By swinging the bar 100 away from the shank 40, cleaning and sterilization of the shank is facilitated.

The bar 100 has an enlarged T-head 120 adjacent the socket 86, the sides of the head slidably engaging the inner surfaces of the walls of the U-shaped shank 40. Said head carries a pair of like parallel forwardly protruding locking pins 122 having rounded tips. Each socket, e.g. the socket 86, at a location opposed to the neck 88 of the socket has two small through passageways 124 spaced apart the same distance as the space between the locking pins 122. The passageways 124 are so located that when their axes are parallel with the elongated axis of the shank 40, they are positioned to slidably pass the pins 122. (See FIGS. 3 and 4.)

Each hemispherical coupling, e.g. the coupling 52, has two passageways 126 located therein on a portion thereof distant from the stub rod 54, the passageways 126 being spaced apart the same distance as the spacing between the passageways 124 in the socket 86 and so positioned that they can be registered with said passageways 124 upon rotation of the ball B in the sockets 86, 86.

To lock each of the blades in a rigid straight-line position, its associated socket 86 is rotated so that the passageways 124 face and are in registry with the locking pins 122 and the hemispherical coupling 52 is rotated so that the passageways 126 are in registry with the passageways 124. Then, by pressure of the thumb and index finger of the operator on the buttons 106, the bar 100 is forced to slide within the shank 40 and towards the socket 86. Consequently, the locking pins 122 enter the socket through the passageways 124 thereby preventing rotation of the socket on its pivot post 90 and the locking pins 122 also enter the passageways 126 in the hemispherical coupling 52, thereby preventing rotation of the coupling relative to its associated socket 86. Thereby, the base of each blade is locked in a rigid straight-line position relative to its shank 40. It will be appreciated that if the branches are disengaged, manipulation of the aforesaid locking means will prevent movement of the base of the associated blade. If this is the fixed blade 48, of course the entire blade would be made immobile. If this is the hinged blade 38, the yoke of said blade is immobilized. The blade 38 itself is left to rotate about the pivot pin 56. If the branches are interengaged, the forward disposition of even one of the buttons will lock both bases, since when the branches are interengaged the complete ball B is formed by the couplings. When the slide buttons are moved away from the sockets, the blades are free to rotate about the two perpendicular axes previously described.

Means is provided to interconnect the ends of the shanks distant from the sockets and to prevent relative sliding movement of the two branches when they are engaged. Said means include an elongated latch 128 (FIGS. 1 and 6) pivoted on one end thereof as by a shouldered screw 130 to a heel 132 of one of the branches 22. The heel 134 of the other branch 24 carries a projecting headed pin 136 for engagement by a notch 138 on the end of the latch 128 distant from the screw 130'. A transversely elongated heel block 140 is secured adjacent the heel 132 of one of the shanks 26, as by a pin 142, and has a projecting portion snugly slidably fitting into the interior of the other shank 40. When the pin 136 is engaged by the notch 138 of the latch 128, and the projecting portion of the heel block 140 is fitted into the end of the shank 40, the two branches 22, 24 are locked against relative movement.

Means is provided for fixing the maximum distance between the hinged blade 38 and the fixed blade 48. Said means also enables an operator to rotate the hinged blade 38 towards the fixed blade 48. The means includes a knob 144 fixed to the outer tip of a threaded shaft 146. The shaft 146 is screwed into a tapped bore 148 in the yoke 58 of the hinged blade 38. The inner tip of the shaft 146 abuts, so as to limit movement of, the pivoted end of the blade 38 and is located so that advancement or retreat of said tip by appropriate rotation of the knob 144 rotates the hinged blade 38 on its pivot pin 56, respectively, towards and away from the fixed blade 48 (see FIG. 6). FIG. 1 illustrates in dot-and-dash lines a position of the blade 38 distant from the blade 48 and in solid lines a position of the hinged blade 38 nearer the blade 48. The hinged blade 38 is limited in its movement toward the fixed blade 48 by abutment of an integral projection 150 against the shaft 80.

The forceps are used by the practitioner in accordance with good medical practice. Each of the branches may be separately utilized, and in this instance alignment of the ball passageways 126 with the socket passageways 124 and movement of the locking pins 122 therein by sliding movement of the buttons 106 immobilizes the associated base of the blade. The branches can be interengaged in the manner previously described. In this condition, with the locking pins inserted into the passageways of the hemispherical couplings and the passageways of the sockets, the bases of both blades are immobilized. By operating the locking means so that said locking pins are moved to a position distanct from said passageways, the blades are free to experience rotation about the mentioned two perpendicular axes. The outside stop 146 for the hinged blade can be set as desired and the hinged blade can be rotated toward the fixed blade as necessary.

It thus will be seen that I have provided an improved instrument which achieves all th objects of my invention and is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein described, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

Having thus described by invention, I claim as new and useful and desire to secure by Letters Patent:

1. In an obstetrical forceps comprising two branches, each branch including an elongated hand-1e and a blade, each blade including a hemispherical coupling, means for detachably engaging the couplings to form a ball, each handle having a socket, means for joining the sockets to form a cage in which the ball is rotatable, and means for rotatably mounting the sockets for rotation relative to the handles about an axis perpendicular to the lengths of the handles: that improvement comprising a passageway in a socket and a passageway in a coupling rotatable into alignment with said first named passageway, a longitudinally reciprocable laterally non-shiftable pin, said passageways "being aligned with the pin only when the blades are in a straight line position relative to the handles, and releasable positive locking means in one operative position locating said pin in said passageways to prevent rotation of said ball and socket and to retain the blades immobile in said in line position and in another operative position withdrawing said pin from said passageways whereby to free the blades for swivelling movement.

2. The improvement in obstetrical forceps as set forth in claim 1 wherein the pin and passageways are located eccentrically with respect to the cage and coupling.

3. The improvement in obstetrical forceps as set forth in claim 1 wherein there is a locking means, a pin and passageways included in each of the branches.

4. The improvement in obstetrical forceps as set forth in claim 3 wherein each releasable positive locking means includes an exposed member located on the exterior of the handle and mounted for manually manipulatable limited sliding movement thereon and an elongated bar fixed on one end to the member and on the other end carrying the pin, said member having one limit of movement corresponding to the one operative position and a second limit of movement corresponding to another position.

5. The improvement in obstetrical forceps as set forth in claim 4 wherein means is provided to mount the bar for pivotal movement away from its associated branch for ease in cleaning and sterilization thereof.

6. In an obstetrical forceps comprising two branches, each branch including an elongated handle and a blade, an articulated universal joint captively attaching each blade to its associated handle for swiveling movement relative thereto about a pair of perpendicular axes, said joint including two sockets forming a spherical cage, means rotatably mounting the cage on a handle for rotary movemeut about a transverse axis and hemisphere attached to each blade, said hemispheres forming a ball seated in the cage, and means detachably interengaging the branches: that improvement comprising means for restricting rotation of the hemispheres in the cage about the axis perpendicular to the axis of rotation of the cage relative to the handle, said rotation limiting means comprising a pin rigidly secured to the socket and extending from its base to its tip in a direction parallel to the axis of rotation of the hemisphere relative to the cage, said pin being disposed eccentrically with respect to said axis of rotation, and a semicircular groove on the surface of said hemisphere, said groove lying on a circle having a diameter less than that of a great circle, said groove opening toward the blade and slidably receiving the pin.

7. The improvement in obstetrical forceps as set forth in claim 6 wherein the hemisphere associated with each branch has a like semicircular groove and the socket associated with each branch as a like pin, said grooves having their ends registered to conjcintly define a continuous circular groove in which both pins are slidable.

References Cited UNITED STATES PATENTS 1,662,169 3/1928 Roderick 128-323 2,219,424 10/1940 La Breck 128-352 2,293,984 8/1942 Kirschbaum 128323 2,639,712 5/1953 Miseo 128323 FOREIGN PATENTS 41,175 6/ 1907 Switzerland.

DALTON L. TRULUCK, Primary Examiner. 

